Wow, if I knew this before I started taking AT classes, I might not have joined this clique. It's so political. I shudder.
To some extent i think the difference in culture with ballroom parties is that ballroom parties are closer to what would be a practica in tango - from what i have read about ballroom dances when they were still social events independent of teachers or schools there were very similar structures - the proverbial dance card is a very efficient tool to only dance with people one wants to.
YMMV, and all that